tarheader: remove init func

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

Author: thaJeztah

tarheader/tarheader.go

@@ -42,9 +42,6 @@ func (fi nosysFileInfo) Sys() interface{} {
 	return nil
 }
 
-// sysStat, if non-nil, populates hdr from system-dependent fields of fi.
-var sysStat func(fi os.FileInfo, hdr *tar.Header) error
-
 // FileInfoHeaderNoLookups creates a partially-populated tar.Header from fi.
 //
 // Compared to the archive/tar.FileInfoHeader function, this function is safe to
@@ -66,8 +63,5 @@ func FileInfoHeaderNoLookups(fi os.FileInfo, link string) (*tar.Header, error) {
 	if err != nil {
 		return nil, err
 	}
-	if sysStat != nil {
-		return hdr, sysStat(fi, hdr)
-	}
-	return hdr, nil
+	return hdr, sysStat(fi, hdr)
 }

tarheader/tarheader_unix.go

@@ -11,13 +11,9 @@ import (
 	"golang.org/x/sys/unix"
 )
 
-func init() {
-	sysStat = statUnix
-}
-
-// statUnix populates hdr from system-dependent fields of fi without performing
+// sysStat populates hdr from system-dependent fields of fi without performing
 // any OS lookups.
-func statUnix(fi os.FileInfo, hdr *tar.Header) error {
+func sysStat(fi os.FileInfo, hdr *tar.Header) error {
 	// Devmajor and Devminor are only needed for special devices.
 
 	// In FreeBSD, RDev for regular files is -1 (unless overridden by FS):

tarheader/tarheader_windows.go

@@ -0,0 +1,12 @@
+package tarheader
+
+import (
+	"archive/tar"
+	"os"
+)
+
+// sysStat populates hdr from system-dependent fields of fi without performing
+// any OS lookups. It is a no-op on Windows.
+func sysStat(os.FileInfo, *tar.Header) error {
+	return nil
+}